CA2095743A1 - Shampoos containing polyglyceryl esters - Google Patents

Abstract

Abstract of the Disclosure A shampoo formulation containing a polyglyceryl ester as the viscosity builder is disclosed. Such shampoos may be formulated to meet the criteria for both baby and adult sham-poos without the need of using ethylene oxide derivatives. By tailoring the polyglyceryl ester employed, a pearlescent appearance can be created and characteristics such as viscosity and clarity may be affected.

Description

,~9~7'~3 ~:

SHAMPOOS CONTAINING POLYGLYCERYL ESThRS ~;

It is well known that shampoos, to be marketable, must meet certain strinyent requirement3 in addition to their neces~ary detergent properties. The~e requirement~ are to some degrae dependent on which of the two ~ajor area3 of application they are to be used in. In one area, i.e., for baby shampoos, it is desirable that they have outstanding clarity, a con-s trolled range of viscosity, extremely low irritability, and ;~
rapid foaming.
In contrast, for adult formulations, opaque (even pearlescent) `~
propertie~ are favored, high viscosity i~ preferred, mildness (while still nece~sary) i9 a less stringent requirement, and conditioning qualities are sought.
It is well known that shampoos not irritating to theeyes can be ~ormulated with certain ratios of ethoxylated ~;~ anionic and amphoteric detergents in comhination with other highly `~
ethoxylated ingrediPnt~. Systems of this type are usually thickened with high molecular weight ethoxylated ester3 such as i-~ PEG 6000 distearate or PEG 80 sorbitan stearate. See U.S.
Patent ~o. 4,177,171. The u3e of the high molecular weight ethoxylat~d esters i3 especially desired in baby shampoos ~
30 because of the importance of viscosi~y control and irritation ~;
reduction To achieve the desired viscosity, mild shampoos have been thickened with gums and polymers. In recent years cation-ic polymers, and especially cationic cellulosic gum~, have been popular becau3e they provide conditioning propertie as well as vi3cosity. See U.S. Patent No. 3,962,418. Unfortunately, the ~ -cationic polymers and gums are perceived as having irritation :
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,, ' ' :' . ' , :' potential and are generally avoided in formulating very mild ~aby shampoos.
In yet another approach, U.S. Patent No. 4,426,310 teache~ that a mild shampoo can be thickened by selecting an 5 optimum ratio of anionic and amphoteric detergent3. Shampoos of thls type u~ually contain high levels of ethoxylated nonion-ics ~uch as Polysorbate 20 to achieve low irritation scores.
One drawback of formulations dependent on ethylene oxide derivatives i~ that the~e derivatives often contain 10 or more ppm of 1,4-dioxane, an impurity which has been iden~ified a~ a carcinogen. Another drawback is dependence upon the use of PEG 6000 DS, an expensive ethoxylate-containing ester that i3 troublesome to both manufacture and handle because of its inherent high visco~ity.
More recen~ly, in U.S. Patent 5,130,056, it i~ taught that C8-CI8 fatty acid monoesters of diglycerol and/or C8-CI6 fa~ty acid diesters of tetraglycerol are u~eful for washing - agents, cleaning agent~, and toiletries, including ~hower -~ preparations, bubble bath preparations, liquid hand cleanRers, and hair shampoos. While these materials meet dermatological and toxicological requirements and, further, are biodegradable they have not been found ~atisfactory for building broad ~- viscosity ranges to the extent desirable for commPrcial formu-;~ lation~.
In light of the foregoing, it is obviously de~irable to formulate baby shampoos which a~e entirely free of ethylene ~- oxide derivatives and adult shampoos devoid of high moIecular -~- weight ethoxylated e~ters.
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In accordance with the instan~ invention, it has now been di~covered that certain high molecular weight polyglyceryl esters (PGEs) can be effectively used to achieve the desired visco~ity in low- and mild-irritation shampoos. Based on the total shampoo formulation, from 1 to 10 wt. %, preferably from .~ :
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1 to 3 wt. %, of the PGEs are used. The resultant shampoos, by selection of ~he appropriate PGE and control of the amount used, can be formulated with viscosities ranging from 200 cps to 8000 cps without the need of including ethylene oxide derivatives in the formulation. Generally the baby shampoos of the invention have from 10 to 25 wt. ~ solids, while the adult shampoos contain from 8 to 30 wt. ~.
The specific viscosity desired, as i9 understood by those skilled in the art, is dependent on the end use applica-1~ tion. It is generally accepted that baby shampoos have ViSC09-ities in the 600 cp~ to 2000 cps range, with 1000 Cp8 to 1500 -cps being the range of choice. Mild adult shampoos will often be formulated to fall in the 1000 Cp5 to 8000 Cp9 viscogity range and some family shampoos are thickened to the gel stage.
The polyglyceryl e3ters of this invention are capable of producing viscosities which range from a few hundred to thou-sands of centipoise. For example, decaglyceryl monooleate, by ; varying the amount used, can build shampoo vi~co~ities from 200 to 5000 cps in baby shampoo formulations and from 2000 cps to -~
over 20000 cps with a desired range of 3000 cps to 8000 cps in typical adult formulations. As will be explained hereafter, the PGEs may also be used to obtain the lower viscosities used in baby shampoo formulations.
The polyglyceryl esters are ideal visco3ity-building additives because they are extremely saf~ and mild. Not only are they free of 1,4-dioxane, but the derivatives up to and including the decaglyceryl esters are approved as food addi-tives by the FDA. A further advantage i9 that they are avail-able from safe renewable resources, namely, glycerin and fatty acids. These basic raw materials, in turn, can be obtained, if so desired, strictly from non-animal sources~
It has been further discovered that certain PGEs offer, in addition to viscosity building and control, other benefits such as pearle~cence, formulation stabilization, and mild conditioning properties. Because of the multiplicity of ~:, :' .: ' ' ' : ~ ~, : ' . ,.: : "

2~7'~3 these benefit~, formulations may be prepared containing PGEs which markedly reduce the number of ingredients from a~ many as ten or twelve to as few as six or seven.

The polyglyceryl ester~ of the subject invention may be represented by the following general formula:
R50CH2 - CH ( oR4 ) - CH2 - ( 0 - CH2 CH ( oR3 ) - CH2 ) o - 0 - CH2 - CH ( oR2 ) - CH20RI, wherein R i9 hydrogen or an acyl group (R-C0-) of a fatty acid ~ 10 moiety having from 8 to 22 carbon atoms, the number of R groups ;~ is broadly from 1 to 14 and preferably from 1 to 12, and n i9 from 4 to 10.
The backbone i~ generally prepared by a condensation reaction which gives a normal distribution pattern in the final polymer. The average number of glycerin units in the base polyol will always total n~2. Generally, the polyglycerols used in the formulations of the invention have a molecular weight of from 300 to 1000, preferably from 500 to ~00.
The fatty acid u~ed to prepare the PGE can be select-ed from a broad range of structural types such as straight `-~ chain or branched and saturated or unsaturated. In ~ome cases, ~' the fatty acid chain length distribution will be a specific blend or will match that found in natural oils such a~, for ~; examplel almond or sunflower oils. The preferred fatty acids have from 14 to 18 carbon atoms. The straight-chain 18-carbon acid is the most de~irable.
In tha case of baby shampoos, the polyglyceryl esters which provide the be t viscosity building, while at the same time contributing to clear solutions, are ba~ed on hexa- to decaglycerols. The best performance wa~ observed with the decaglyceryl series where approximately 10 moles of glycerin are reacted to form the polyglycerol moiety. The best combina-~ tion of vi9c09ity building and solubility i~ observed with ;~ monoester~. In such ca3es, if one R equal~ a fatty acid -~ 35 moiety, then the other R~ would be hydrogen. It will be .'`'' ~
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2n9~7~3 understood that, in reality, the monoester material is not 100 but in the range of between 30~ and 70% of the composition.
The remainder, based on a statistical distribution, will be di-, tri- or higher esters along with some unreacted polyol. The R groups, in fact, repre~ent a percentage ratio of fatty acid group to hydrogen. In the preferred case, the best performance is observed with the oleates, particularly decaglyceryl monool-eate. Other u~eful PGEs include decaglyceryl dioleate, decagl-yceryl monosunflower-ate, and decaglyceryl monoalmond-ate.
In the case of adult shampoos, the n values may range from 4 (meaning a hexaglyceryl ester) to 10 (meaning a ~`
;~ dodecaglyceryl ester). The best performance is obtained with i~ compounds where n averages from 4 to 8, preferably from 4 to 6, and most desirable ester~ have an average n value of 4.
In the adult shampoos, clarity i9 less important than viscosity and conditioning effects. The PGEs can be used not ~-~ only to develop viscosity and pearlescence, but also to provide other attributes to the shampoo ~uch as conditioning benefits and formulation stability. These optimum benefits are achieved by adjusting the ratios o R to H in the PGE and by selecting an R group with the most appropriate carbon chain length distribution. Preferably, the R groups are straight-chain which have from 12 to 20 carbon atoms. Most desirably, the R
groups have from 16 to 18 carbons. The n-stearate is particu-larly effective.
The total number of R groups depends on the size ofthe polyglycerol polymer. The n is broadly from 4 to 8, preferably from 4 to 6. For example, where n=4, the base ~polymer would be hexaglycerol and the total number of ester ; 30 linkages (R groups) pos3ible would be eight. To illustrate further, if the R groups derived from oleic acid are attached to a polyglycerol and n=8, the final product may have 12 ester units. The resultant compound would be decaglyceryl ; dodecaoleate. In adult type shampoos, the best re~ults are ~35 observed with hexaglyceryl distearate which contains 2 R groups ., ~'.

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',: ' , 6 2~957~3 having C-18 carbon chains. Other PGEs which may be used are ~:
decaglyc~ryl monostearate, octaglyceryl dilaurate, and hexagly-ceryl monopalmitate and dipalmitate.
While the expression "adult shampoo" and "baby shampoo" are used above, it will be understood that the defini-tions of these formulations may indeed overlap. Also, while it is mandatory that baby shampoos be mild to achieve market acceptance, the adult shampoos of the invention may also have this attribute.
Essential components of all shampoos are surfactants.
These may be selected from a wide variety of synthetic anionic, zwitterionic, and nonionic types. In mild- or low-irritation ;~ shampoos, the total anionic surfactant concentration will :: ~
usually be minimized to the extent feasible.

Anionic Surfactants The preferred anionic surfactants are the water-; soluble salts of Cl0 to C14 fatty alcohol sulfates. Thase develop a rich foam. The sodium salts are most prevalen~ but other soluble salts include potassium, ammonium, diethanol- and triethanolammonium cations.
Sodium lauryl sulfate i~ most preferred. For a baby shampoo, the concentration range of the anionic on a 100~ total formulation weight basls is in the range of 1% to 3%. The best 25 working le~el i9 between 2~ and 2.5~. For an adult shampoo, ;~
from 5 to 20~, preferably from 8 to 18~, i9 used. The anionic concentration is minimized by a high~loading of zwitterionic surfactants to the extent~practical to help insure that its irritation potential is suppressed.
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' - ., . , . : , 2~9~7~3 As a general matter, anionic surfactants are exempli-fied by the alkali metal salts of organic ~ulfuric reaction products having in their molecular structure an alkyl radical containing from 8 to 22 carbon atoms and a sulfonic acid or sulfuric acid ester radical (included in the term alkyl is the alkyl portion of higher acyl radicals). Preferred alkyl sulfates are sodium coconut oil fatty acid monoglyceride ;-~
sulfate and sulfonates and those obtained by sulfating higher alcohols, i.e., those containing C8 to C18 carbon atoms. Other examples are ~odium or potassium salts of sulfuric acid esters of the reaction product of 1 mole of a higher fatty alcohol (e.g., tallow or coconut oil alcohols) and 1 to 12 moles of ethylene oxide; sodium or potassium salts of alkyl phenol ethylene oxide ether sulfate with 1 to 10 units of ethylene ~ ;
oxide per molecule and in which the alkyl radicals contain from 8 to 12 carban atoms, sodium alkyl glyceryl ether sulfonates;
the reaction product of fatty acids having from 10 to 22 carbon ;~
atom~ esterified with isethionic acid and neutralized with sodium hydroxide; and water-soluble salt of condensation products of fatty acids with sarcosine.
''`'''''- :' - Zwitterionic Surfactants The zwitterionic surfactants make up the bulk of the ; low-irritation shampoo. The main ingredient is identified as cocamidopropyl betaine in the CTFA dictionary and the use level . ~ , for a baby shampoo ranges from about 3 to about 10 wt. ~ on a 100~ actives basis. The preferred range runs from approximate- ,~

~ ' ` ' , ., , , . . , - ~ , , , . , ~ , , : , 2~7~ 3 ly 4~ to 9%. For an adult shampoo, the broad range i9 from 5 to 25%, with from 10 to 20~ being preferred. Other alkyl-amidopropyl betaines can be used having alkyl groups derived from ClO to C~6 fatty acids. The corresponding alkylamidopropyl S ~ultaine~ are acceptable, especially cocamidopropyl sultaine.
Additional zwitterionic surfactants which can be used r;' in the present invention are substituted imidazolines. The specific, preferred surfactants are described in the CTFA
;~ dictionary as sodium cocoamphoacetate and disodium 10 cocoamphodiacetate. In addition to, or in place of, the coco-derived imidazolines, one can use similar structures prepared from ClO to C~6 fatty acids. The active content of imidazoline surfactant, either as a single reagent or as a blend, runs from about 1.5% to about 2.5~. These materials do not have a 15 critical impact on product performance, so a preferred use ~-~
level i9 not necessary. The imidazoline surfactants are included in the 3hampoo development to provide irritation reduction (increase mildness) and to give some improvement in t hair conditioning.
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Zwitterionic surfactants are exemplified by deriva-tives of aliphatic ~uaternary ammonium, phosphonium, and : sulfonium compounds, in which the aliphatic radicals are ~; straight chain or branched, and wherein one of the aliphatic ubstituents contains from about 8 to 18 carbon atoms and one contain3 an anionic water-solubilizing group, e.g., carboxyl, sulfonate, sulfate, pho~phate, or pho~phonate. A general ' ~ formula for these compounds is:
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(R3) x R2 y(+) CH2 R4 Z(-) wherein R2 is an alkyl, alkenyl, or hydroxyalkyl radical of :~ from about 8 to about 18 carbon atom~. They may contain up to about 10 ethylene oxide moietie~ and up to 1 glyceryl moiety.
Y is a nitrogen, phosphorus, or sulfur atom; R3 is an alkyl or ; monohydrox~alkyl group containing 1 to about 3 carbon atoms; X
is 1 when Y i8 a sulfur atom and 2 when Y i9 a nitrogen or phosphorus atom; R4 i~ an alkylene or hydroxyalkylene of from about 1 to about 4 carbon atoms; and 2 i9 a carboxylate, sulfonate, sulfate, phosphonate, or phosphate group.
Examples include~
4-[N,N-di(2-hydroxyethyl~-N-octadecylammonio~-butane-l-carbox-: ylate;
`~ 15 5-[S-3-hydroxypropyl-S-hexadecylsulfonio]-3-hydroxypentane-1- ::
sulfate; ::
~: 3-[P,P-diethyl-P-3,6,9-trioxatetradecoxylphosphonio]-2-hydroxylpropane-l-phosphate;

3-[N,N-dipropyl-N-3-dodecoxy-2-hyclroxypropylammonio]-propane-1-. 20 pho~phonate;
- 3-(N,N-dimethyl-N-hexadecylammonio)propane-l-sulfonate;
3-(N,N-dimethyl-N-hexadecylammonio)-2-hydroxypropane-1-sulfo-~`~ nate;

4-[N,N-di(2-hydroxyethyl)-N-(2-hydroxydodecyl)ammonio]-butane-25 l-carboxylate; `~
3-[S-ethyl-S-(3-dodecoxy-2-hydroxypropyl)sulfonio]-propane-1-phosphate;

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~9~7'13 3-[P,P-dimethyl-P-dodecylphosphonio]-propane-l-phosphonate; and 5-[N,N-di(3-hydroxypropyl)-N-hexadecylammonio]-2-hydroxypentane-1- 8ul fate.
Examples of other betaines useful herein include the 5 high alkyl betaines such as:
coco dimethyl carboxymethyl betaine, lauryl dimethyl carboxymethyl betaine, lauryl dimethyl alpha-carboxyethyl betaine, cetyl dimethyl carboxymethyl betaine, ;
10 lauryl bis-(2-hydroxyethyl)carboxymethyl betaine, stearyl bis-(2-hydroxypropyl)carboxymethyl betaine, oleyl dimethyl gamma-carbox~propyl betaine, lauryl bis-(2-hydroxyprop~l)alpha-carbo~yethyl betaine, etc.
The sulfobetaine~ may be represented by:
15 coco dimethyl sulfopropyl betaine, -; stearyl dimethyl sulfopropyl betaine, lauryl dimethyl sulfoethyl betalne, lauryl bis-(2-hydroxyethyl)sulfopropyl betaine and the like.
Amido betaines and amidosulfo betaines, wherein the RCONH(CH2) 3 s 20 radical is attached to the nitrogen atom of the betaine, are t~
al~o useful in this invention.
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Amphoteric Surfactant~
Examples of amphoteric surfactants which can be u~ed in the compo~itions of the present invention are derivatives of aliphatic ~econdary and tertiary amines in which the aliphatic ~; radical i~ straight chain or branched and wherein one of the ~' ' ;

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aliphatic substituents contains from about 8 to about 18 carbon atoms and one contains an anionic water-solubilizing group, e.g., carboxy, sulfonate, sulfate, pho~phate, or phosphonate.
Examples of these compounds are sodium 3-dodecylamino-propionate, sodium 3-dodecylaminopropane ~ulfonate, and N-alkyltaurines such as the reaction product of dodecylamine and -:
~odium isethionate, and N-higher alkyl aspartic acids.

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12 2 ~ 3 Nonionic Surfactants Nonionic surfactants, which are preferably used in combination with an anionic, amphoteric or zwitterionic surfac-tant, can ~e broadly defined as compound~ produced by the condensation of a hydrophilic alkylene oxide group with an aliphatic or alkyl aromatic hydrophobic compound. Examples of preferred classes of nonionic surfactants are:
1. Long chain tertiary amine oxides corresponding to the following general formula:
R~R2R3N ~ 0 i wherein Rl contain~ an alkyl, alkenyl or monohydroxy alkyl radical of from about 8 to about 18 carbon atoms, up to about 10 ethylene oxide moietie~, and up to 1 glyceryl moiety, and and R3 contain from 1 to about 3 carbon atoms and up to about 1 15 hydroxy group, e.g., methyl, ethyl, propyl, hydroxyethyl, or ~;
hydrox~propyl radicals. Examples of amine oxides suitable for use in this inventlon include:
dimethyldodecylamine oxide, " oleyldi(2-hydroxyethyl)amine oxide, 20 dimethyloctylamine oxide, dimethyldecylamine oxide, dimethyltetradecylamine oxide, 3,6,9-trioxaheptadecyldiethylamine oxide, di(2-hydroxyethyl)tetradecylamine oxide, ~ 25 2-dodecoxyethyldimethylamine oxide, :~ 3-dodecoxy-2-hydroxypropyldi(3-hydroxypropyl)ami.ne oxide, and dimethylhexadecylamine oxide.
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7 '1 3 ; 2~ Long chain tertiary phosphine oxides corresponding to the following general formula:
RR'R"P ~ O
wherein R contains an alkyl, alkenyl or monohydroxyalkyl radical ranging from 8 to 18 carbon atoms in chain length, up to about 10 ethylene oxide moieties, and up to 1 glyceryl moiety and R' and R" are each alkyl or monohydroxyalkyl groups containing from 1 to 3 carbon atoms. Examples of suitable phosphine oxides are: ~
10 dodecyldimethylphosphine oxide, -~:
~ tetradecyldimethylphosphine oxide, ;~ tetradecylmethylethylphosphine oxide, ~;~
`~ 3,6,9-trioxaoctadecyldimethylphosphine oxide, cetyldimethylphosphine oxide, i~ 15 3-dodecoxy-2-hydroxypropyldi(2-hydroxyethyl)phosphine oxide, ~tearyldimethylphosphine oxide, cetylethylpropylphosphine oxide, ;~
oleyldiethylpho3phine oxide, .~ .
`~ dodecyldiethylphosphine oxide, 20 tetradecyldiethylphosphine oxide, : :
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;:~ dodecyldipropylphosphine oxide, , ~- dodecyldithydro~ymethyl)phosphine oxide, :~

: dodecyldi(2-hydroxyethyljphosphine oxide, tetradecylmethyl-2-hydroxypropylphosphine oxide, ;~

oleyldimethylphosphine oxide, and ~ 2-hydroxydodecyldimethylphosphine oxide.

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'~ ' ' ,,: ' ', : , 7 ~1 3 3. ~ong chain dialkyl sulfoxides containiny one short chain alkyl or hydroxy alkyl radical of 1 to about 3 carbon atoms (u~ually methyl) and one long hydrophobic chain which contains alkyl, alkenyl, hydroxy alkyl, or keto alkyl radlcals containing from about 8 to about 20 carbon atoms, up to about 10 ethylene oxide moieties, and up to 1 glyceryl moiety.
Examples include: octadecyl methyl sulfoxide, 2-ketotridecyl methyl sulfoxide, 3,6,9-trioxaoctadecyl 2-hydroxyethyl sulfox-ide, dodecyl methyl sulfoxide, oleyl 3-hydroxypropyl sulfoxide, tetradecyl methyl sulfoxide, 3-methoxytridecyl methyl sulfox-ide, 3-hydroxytridecyl methyl ~ulfoxide, 3-hydroxy-4-dodecoxybutyl methyl 9ul foxide.
Though not generaIly desirable a~ ingredients in the formulations of the invention, limited amount~ of the following ,~
ethylene oxide derivatives may be used as the nonionic surfac-tant:
1. The polyethylene oxide condensates of alkyl -~ phenols, e.g., the condensation products of alkyl phenols ~`~ having an alkyl group containing from about 6 to 12 carbon atoms in either a ~traight chain or branched chain configura-tion, with ethylene oxide, the said ethylene oxide being ~ present in amounts equal to 10 to 60 moles o~ ethylene oxide `~ per mole of alkyI phenol. The alkyl substituent in such compounds may be derived from polymerized propylene diisobutylene, octane, or nonane.
2. Those derived from the condensation of ethylene oxide with the product resulting from the reaction of propylene ~.

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' 20~.~7~3 oxide and ethylene diamine products which may be varied in composition depending upon the balance between the hydrophobic and hydrophilic elements which is desired. For example, com-pounds containing from about 40% to about 80% polyoxyethylene by weight and having a molecular weight of from about 5,000 to about 11,000 resulting from the reaction of ethylene oxide groups with a hydrophobic base constituted of the reaction product of ethylene diamine and excess propylene oxide, said base having a molecular weight of the order of 2,500 to 3,000, ; 10 are satisfactory.
3. The condensation product of straight or branched chain aliphatic alcohols having from 8 to 18 carbon atoms with ethylene oxide, e.g., a coconut alcohol ethylene oxide conden~
~ate having from 10 to 30 moles of ethylene oxide per mole of 15 coconut alcohol, the coconut alcohol fraction having from 10 to ~-~` 14 carbon atoms.
: ~ ' ;~ In addition to the basic components described above, ~; the present invention may contain a variety o~ optional ingre- ~-~
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dients which are generally used in shampoos. These include ~`~ polyols, preservatives, silicon fluids, su~pending agents, ;~
dyes, fragrances, preservatives, and buffering or pH control agents. For baby shampoos, such agents should be water-soluble --~
to insure product clarity and not be irritating to skin or eyes.
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,' "' ' ' , ' , ~ , ' 16 2 ~9 ~7'13 Polyols A further optional ingredient involves the addition oE a polyol such as glycerin, propylene glycol, sorbitol or other cosmetically acceptable glycols. Polyols are added to provide auxiliary benefits such as secondary viscosity control, skin and hair moisturizing, bulking, or feel modification. In the shampoo products described below, glycerin was judged to be ` the best candidate to provide a better feel.
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Preservatives Preservatives include dimethyl dimethylolhydantoin , ~
(DMDMH), DMDMH/iodopropynyl-butyl carbamate (Glydant Plusj a registered trademark of Lonza Inc.), benzyl alcohol, methyl paraben, propyl paraben and imidazolidinyl urea. Of course, ~;~ there are many addltional preservatives that will function ~;~ effectively in shampoos.

Buffering and pH-Control Agents It is generally desirable to adjust mild shampoos such that the pH falls in the 5.5 to 7.5 range. In the formu-lation~ of the i~vention, the preferred pH range i~ 6.5 to 7Ø

~; This can be adiu~ted, as needed, with either a base such as ,,, ~ , .
- ~odium hydroxide or sodium carbonate or an acid such as citric ~ 25 acid, succinic acid, or phosphoric acid.
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2 ~ ~ ~ 7 ~ 3 Silicone fluids Non-volatile silicones are the most suitable sili~
cone fluids that may be used in the present compositions. The non-volatile silicone fluid may be either a polyalkyl ~iloxane, a polyaryl siloxane, a polyalkylaryl siloxane or a polyether siloxane copolymer and i9 present at a levPl of from about 0.1 to about 10.00~, preferably from about 0.5% to about 5.0 Mixtures of these fluids may also be u3ed. The dispersed sili-cone particles should also be insoluble in the shampoo matrix.
The essentially non-volatile polyalkyl ~iloxane fluid~ ~hat may be used include, for example, polydimethyl siloxanes with visco~ities ranging from about 5 to 600,000 ; centis~okes at 250C. These siloxanes are available, for ~, . ..
example, from the General Electric Company as the Viscasil series and from Dow Corning as the. Dow Corning 200 series. The ~`~
viscosity can be measured by means of a glas~ capillary viscom-eter as ~et forth in Dow Corning Corporate Test Method CTM0004, July 20, 1970. Pre~erably the viscosity ranges from about 350 :
centistokes to about 100,000 centlstokes.

The essentially non-volatile polyalkylaryl siloxane ~- fluids that may be used include/ for example, polymethylphenyl siloxanes having viscositie~ of about 15 to 30,000 centistokes : .
at 250C. These siloxanes are available, for example, from the General Electric Company as SF 1075 methyl phenyl fluid or from Dow Corning a~ 556 C03metic Grade Fluid.
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:.: ~-: -., . : ~ :, : , , 209.~ 7 L~ 3 1~ -The e~sentially non-volatile polyether siloxane copolymer that may be used i~, for example, a polypropylene oxide modified dimethyl polysiloxane (e.g., Dow Corning DC-1248), although ethylene oxide or mix~ures of ethylene oxide j~ 5 and propylene oxide may also b~ used.
References disclosing suitable silicone fluids include the previously mentioned U.S. Patent No. 2,826,551 to Geen; U.S. Patent No. 3,964,500, June 22, 1976, to Drakoff;
~:
; U.S. Patent No. 4,364,837 to Pader, and British Patent No.
`~; 10 849,433 to Wools~on. All of these patents are incorporated herein by reference. Also incorporated herein by reference is Silicon Compounds, distributed by Petrarch Systems, Inc., 1984.
`- This reference provides a very good listing of suitable sili-cone materials.
Another silicone material found especially useful in the present composition3 to provide good dry combing is a sili-cone gum. Silicone gums are described by Petrarch and others, including U.S. Patent No. 4,152,416, May 1, 1979, to Spitzer et ,~ al. and Noll, Walter, Chemistry and Technology of Silicones, New York: Academic Press, 1968. Also describing silicone gums are General Electric Silicone Rubber Product Data Sheets SE 30, SE 33, SE 54, and SE 76. All of these described references are incorporated herein by reference. "Silicone gum" materials denote high molecular weight polydiorgano~iloxanes having a '1^' :
-~- 25 mass molecular weight of from about 200,000 to about 1,000,000.
Specific examples include polydimethylsiloxane, (polydimethyl-siloxane) (methylvinylsiloxane) copolymer, ,~' ...

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, 19 ~9~7'13 poly(dimethylsiloxane) (diphenyl) (methylvinylsiloxane) copoly-mer and mixtureq thereof.
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O~tional Component~ ;
It has been discovered that PGEs provide multiple benefits such as ~hickening, pearlizing, suspending, stabiliz--: ~
ing, and emulsification. In many cases, the PGEs can be used to replace all or part of gums and polymers that are used to develop viscosity. Certain PGEs can be used to replace ethyl-ene glycol stearates where a pearl effect is desired. Other pearlizing agents may also be replaced. PGEs may be used in place of noniGnic surfactants and xanthan and guar gums to provide suspension properties. Other optional materials are described below.
The suspending agent useful in the present composi-tions can be any of several long chain acyl derivative materi--`` als or mixtures of such materials. Included are ethylene glycol e~ters of fatty acids having from about 16 to about 22 carbon atoms. Preferred are the ethylene glycol stearates, ~ -~
both mono- and distearate, but particularly the distearatè
containing le93 than about 7~ of the monostearate. Other , su~pendlng agents found useful are alkanol amides of fatty acid~, ha~ing from about 16 to a~out 22 carbon atoms, prefera-bly about 16 to 18 carbon atoms. Preferred alkanol amides are 25 stearic monoethanolamide, stearic diethanolamide, stearic ~;
monoisopropanolamide, and stearic monoethanolamide stearate. ;
Other long chain acyl derivatives include long chain ester~ of ~

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long chain fatty acids ~e.g., stearyl stearate, cetyl palmi-tate, etc.), glyceryl e~ters (e.g., glyceryl di~tearate), and long chain esters of long chain alkanol amides (e.g., stearamide DEA distearate, stearamide MEA stearate).
Still other suitable suspending agents are alkyl (C
22) dimethyl amine oxides such as ~tearyl dimethyl amine oxide.
If the compositions contain an amine oxide or a long chain acyl derivative as a surfactant, the suspending function could also be provided and additional suspending agent may not be needed iE the level of those materials are at least the minimum level given below.
~ The ~uspending agent is present at a level of from -~ about 0.50% to about 5.0%, preferably from about 0.5% to about 3.0%. The su~pending agent serves to as~ist in suspending the silicone material and may give pearlescence to the product.
Mixtures of suspending agents are also suitable for use in the compositions of this invention.
Xanthan gum can also be u3ed to suspend the silicone ~ ~`
fluid. This biosynthetic gum material is commercially avail-; 20 able and i~ a hetero-polysaccharide with a molecular weight of greater than l million. It i~ believed to contain D-glucose, D-mannose, and D-glucuronate in the molar ratio of 2.8:2.0:2Ø
The polysaccharide is partially acetylated with a 4.7~ acetyl.
Thls and other information 1s found in Roy L. Whistler, Ed., Industrial Gums - Polysaccharides~and Their Derivatives (New York: Academic Pre , 1973). Kelco, a Division of Merck & Co., Inc. offers xanthan gum as Keltrol~. The gum i~ present at a ~-,~,~. .
-,~,.; : .

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7 ~ 3 level of from about 0.3~ to about 3%, preferably from ahout 0.4~ to about 1.2%, in the compositions of the present inven-tion.
Cationic surfactants such as cetyl trimethyl ammonium chloride, lauryl trimethyl ammonium chloride, tricetyl methyl ammonium chloride, stearyldimethyl benzyl ammonium chloride, and di(partially hydrogenated tallow)dimethylammonium chloride may also be added.
Supplemental thickeners and viscosity modifiers ~ -include sodium chloride, sodium sulfate, polyvinyl alcohol, and ethyl alcohol. Perfumes, dyes, and sequestering agents such as disodium ethyl~nediamine tetraacetate may also be used. Such agents generally are used individually at a level of from about -0.01% to about 10~, preferably from about 0.5% to about 5.0% by weight of the compo~ition.
~. .
The examples below are given solely for the purpose of illustration and are not intended to limit the scope of the present invention. Many variations are possible without departing from the spirit and scope of the invention.
In the examples, deioniz-ed water is weighed into a suitable container and the anionic surfactant is mixed in .~
gently to minimize foam and aeration. The betaine, the ampho-;~ teric surfactants, and the polyol are added with stirring in the order listed. The clear shampoo blend is heated and, when the temperature reaches between 700C and 750C, the polyglyceryl ester is added. After the polyglyceryl ester is completely dissolved and the system is clear, the heat is discontin~ed and ' ~
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, 22 ~J~ 3 replaced with cooling. Preservatives, fragrance, and dyes are added when the batch has cooled to 45~C or lower. When the batch returns to room temperature, compensation i9 made for evaporated water and the pH i3 adjusted to the 6.5 to 7.0 range.
Examples I and II compare a market-leading baby shampoo which is known to have a zero score in the Draize test and a harsh commercial shampoo which is irritating to the eyes.

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A clear, mild shampoo free of ethylene oxide adducts and thickened with polyglyceryl ester and having the following composition was prepared as described above.

. ~ . . .
Components Part~ by Weight _ . : :
Sodium lauryl sulfate 6.00 , . ___ : Cocamidopropyl betaine 16.00 ; Sodium cocoamphoacetate 2.00 = . . . _ ~_ ___________ e _ -- . ______ 10 Disodium cocoamphodlacetate 2 00 Glycerin 2.50 . ~ _ _ _ .
.~ Decaglyceryl monooleate 1.50 _ _ .
` Glydant~ Plus ` 0.05 ' ~' . . _ . _ . _ ~............. Fragrance 0.50 i ,~ . _ _ ~ 15 . Deionized water and dyes 69.45 '~ ~' . ;
:~ The pH was adju~ted to 6.6 with citric acid. The viscosity, :~ measured with a Brookfield in~trument, Model RVT, was la50 cp~.

Using the Organogenesis test, ~he cell viability after 5 ~;

. 20 minutes exposure was 81~. In contrast, the leading formulation ~ of baby shampoo containing ethylene oxide derivatives had only .~ a 73~ cell viability, while a conventional adult shampoo scored ;
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2 f3 ~ 3 6~. This lllustrate~ the mildnes~ of the shampoo of the inven-tion.
As a comparison, the decaglyceryl monooleate was omitted from the above formulation and the visco~ity dropped to 1100 cps. This clearly demonstrates the thickening power of ~he PGE. ~-The non-irritating performance of the shampoo~ of the invention was demonstrated by in vitro methodology which was ; developed hy Organogenesis, Inc. of Cambridge, MA, and is based on the use of cultured living cell~ which respond like human skin. In this test, one measures the percentage of cells that survive exposure to a foreign compound over a relatively ~hort time period. The test results are not directly correlated to Draize eye test scores, but the degree of non-irritancy can be estimated by comparison with known materials.
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The ethylene oxide (EO) free product of Example I
(1.5~ PGE) and a similarly constituted product with 10~ PGE
were compared with the market leading baby and adult shampoos.
The baby shampoo (J&J) is sold by Johnson & Johnson Consumer Products Inc., Spellman, NJ. This product contains water, PEG-80 sorbitan laurate, cocamidopropyl betaine, sodium trideceth sulfate, sodium chloride, lauroamphoglycinate, PEG-150 distearate, sodium laureth-13 carboxylate, fragrance, citric acid, quaternium 15, tetrasodium EDTA, D&C yellow No. 10, and D&C orange No. 4. The adult shampoo i~ Prell~, sold by Procter ~; & Gamble of Cincinnati, Ohio. It contains water, ammonium .~
laureth sulfate, ammonium lauryl sulfate, glycol distearate, cocamide MEA, dimethicone, citric acid, sodium hydroxide, fragrances, EDTA, ammonium xylenesulfonate, ammonium chloride, methylchloroisothiazolinone, methylisothiazolinone, FD&C blue No. 1, and FD&C yellow No. 5.

~ 1 `; The J&J baby shampoo i9 known to have a zero score in the . :
~-` Draize test. Th~ Prell adult shampoo i9 characterized as harsh ~
: ~ :
and is irritating to the eye~. The results are sho~n in Table ~` Io .,.,,~ ;~:.

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2 ~ 9 ~ 7 ~ 3 TABLE I

Shampoo Sample % Cell Viability (1% Conce~tration) ~5 min Er~1~o~re~
5 Baby shampoo (J&J) 73 EO-free shampoo (1.5~ PGE)~ 81 EO-free shampoo ~10~ PGE)* 95 _ . -- .
, Adult shampoo (Prell~) 6 . __ _ _ .
* Decaglyceryl monooleate . The hi.gher the level (~) of cell viability, the safer or more :~ non-irritating the sample. The data in Table I demonstrate . that PGEs, in this case decaglyceryl monooleate, have the : ability to mitigate irritation.
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An additional clear, mild product containing no ethylene oxide adducts and mo~t suitable for the baby shampoo market is described in the following table: -':~
. Component~ Part~ by~Weight ~
9~di~ 5.00 ¦
.~ Cocamidopropyl betaine 11.00 Sodium cocoamphoacetate 3.00 ¦ ;~
10 Disodlum cocoamphodiacetate 3.00 ¦ :~

Glycerin 2.50 - ¦
-- _ .............. .. ~__ ~:
~ Decaglyceryl monooleate 1.50 ~
.... _.___~ ~ 7 . Glydant~ Plus 0.05 ¦ 1~ ~
. ~. ~ _ . . ...... ~_ ~............. Fragrance 0.50 ~ :~
;- 15 Deionized water and dyes 73.45 `~;
The pH was adju~ted to 6.6 with citric acid. The viscosity, ;
measured with a Brookfleld instrument, Model RVT, was 6100 Cp9.
`' When the polyglyceryl:ester was omitted, the viscosity of the ::~ 20 Example III shampoo dropped to 4000 cps. :~
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A "comb-out" study was conducted on hair tresses to determine performance properties of the EO~free baby shampoo ; 5 (Example III) Three formulas of the invention were evaluated against the market leading baby shampoo (J&J). The ingredients which varied in the E0-free formulas were glycerine, sorbitol, and propylene glycol. The following procedure was used in preparing all hair tresses for evaluation:
~ 10 (1) Rinse in lukewarm water.
`~ (2) Comb wet, six times.
(3) Apply a measured amount of test shampoo. ~-~
(4) Lather and rinse.
(5) Comb wet, six times.
(6) Blow-dry and evaluate for tactile feel.
The results of the overall evaluation rated the three E0-free baby shampoos as being better in conditioning proper-ties than the market leading baby shampoo. The improved hair feel was readily detectable and prevented a dry matte feel. ~;
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This example demon~trate~ a rnildly pearle~cent "2-in-1" shampoo wherein the pearl effect is derived from hexaglyceryl distearate. The PGE al~o generates the high viscosity.
~, Component~ Parts by Weight :- Ammonium lauryl sulfate 30.00 _ _ _ _ _ , Ammonium laureth sulfate 13.50 ~: ~ . . , 10 ICocarnonoethanolarnlne 1.00 ¦Hexaglyceryl distearate 3.00 Dimethicone 1.00 ~ :
: I . _ _ _ _ _ ~, . ~.. _.
Sodium chloride 0.40 ~ ~
,. I _ _ _ _ Glydant P103 O . 10 ~ ;

: 15 Deionized water 51.00 ;
. --- ..... ~ .. = ~

.,~ The pH wa~ adjusted to 6.41 with citric acid. The viscosity, ~ measured with the Brookfield viscometer, was 7200 cps.
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~9~7'~3 Comparatlve Example The hexaglyceryl distearate was omitted from the product of Rxample V. As a result, the viscosity was much lower and the slight pearlescence was replaced with a hazy, somewhat translucent appearance.

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Ammonium lauryl sulfate 30.00 ~ .
Ammonium laureth sulfate 13.50 _ ~:
Cocamide monoethanolamine 1.00 Dimethicone 1.00 Sodium chloride 0.40 Glydant~ Plus 0.10 e _ _ _ _ ~ Deionized water 54.00 ~
,~ , = _ ;,~.

The pH was adjusted to 6.38 with citric acid. The viscosity was 1900 cps as measured with the Brookfield vi~cometer. This - is too low for a satisfactory adult ~h~mpoo.
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3 1 2 ~ 9 ~ 7 ll 3 Example VI
A product evaluation panel test was conducted to compare the hair performance properties of the 2-in-1 shampoos of this invention against Pert Plus~, a leading conditioning shampoo. The term "2-in-1" i9 used to describe a product that contains both a shampoo and a conditioner. Pert Plus~, market-ed as a "shampoo plus conditioner in one," contains water, ammonium lauryl sulfate, ammonium laureth sulfate~ dimethicone, glycol distearate, ammonium xylenesulfonate, fragrance, cocamide MEA, tricetylmonium chloride, xanthan gum, cetyl alcohol, stearyl alcohol, ~odium chloride, methylchloroisothiazolinone, methylisothiazolinone, sodium citrate, citric acid, D&C green No. 8, D&C yellow No. 10, and .
FD&C blue No. 1.
Thirty panelists evaluated three conditioning sham-poos based on a "~equential monadic" test format. The panel was divided into two groups. The first fifteen panelists ~;
evaluated a 2-in-1 with silicone against the market leader.
~`~ The second fifteen panelists evaluated a 2-in-1 with silicone against a 2--in-1 without silicone, both containing PGE~. The length of the study was two weeks. Specific questionnaires were comple~ed during the evaluation period.
~ The re~ults of the test indicate tha~ the 2-in~
;~ shampoo performs as well as the market leader in foaming, rinse off, and initial manageability to the hair. In comparing the 2-in-1 with and without silicone, the panelists detected conditioning properties in the non-silicone formula. This ~' ' . .
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32 ~ 7~3 suggests that the PGE contributes a conditioning benefit. The :~
incorporation of the PGE also produced the desired effects of pearle~cence, viscosity enhancement, and conditioning proper~
ties to the shampoo.

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Claims (25)

We claim:

1. A shampoo formulation which comprises:
(a) from 1 to 20 wt. % of an anionic surfactant;
(b) from 1 to 10 wt. % of a polyglyceryl ester having the formula:
R5OCH2-CH(OR4)-CH2-(O-CH2 CH(OR3)-CH2)n-O-CH2-CH(OR2)-CHOR1 wherein n is from 4 to 14 and one or more R groups is an acyl group containing from 8 to 22 carbon atoms and the remaining R groups are hydrogen;
said formulation having a viscosity in the range of from 200 to 20,000 centipoise and a pH in the range of from 6.5 to 7.5.

2. The shampoo formulation of claim 1 having a viscosity of from 1000 to 8000 cps and a pH of from 5.5 to 7.5.

3. The shampoo formulation of claim 1 wherein the solids concentration is from 8% to 30%.

4. The shampoo formulation of claim 1 wherein the composition also contains a polyol.

5. The shampoo formulation of claim 4 wherein the polyol is glycerin, propylene glycol, or sorbitol at a concen-tration of from 0.5 to 10 wt. %.

6. The shampoo formulation of claim 1 wherein the polyglyceryl ester is an ester of a straight-chain fatty acid.

7. The shampoo formulation of claim 1 wherein the polyglyceryl ester is a decaglyceryl monooleate, monosunflower-ate ester, hexaglyceryl distearate or dilaurate.

8. The shampoo formulation of claim 1 wherein the composition also contains a zwitterionic surfactant.

9. The shampoo formulation of claim 8 wherein the zwitterionic surfactant is a betaine.

10. The shampoo formulation of claim 1 wherein the anionic surfactant is sodium lauryl sulfate.

11. The shampoo formulation of claim 10 wherein the zwitterionic surfactant is cocamidopropyl betaine, a sodium cocoamphoacetate, or a disodium cocoamphodiacetate.

12. A baby shampoo formulation which comprises:
(a) from 1 to 5 wt. % of an anionic surfactant;
(b) from 1 to 10 wt. % of a polyglyceryl ester having the formula:
R5OCH2-CH(OR4)-CH2-(O-CH2 CH(OR3)-CH2)n-O-CH2-CH(OR2)-CH2OR1 wherein n is from 4 to 14 and one or more R groups is an acyl group containing from 8 to 22 carbon atoms and the remaining R groups are hydrogen;
(c) from 3 to 10 wt. % of a zwitterionic surfac-tant;

said formulation having a viscosity in the range of from 200 to 5,000 centipoise and a pH in the range of from 6.5 to 7.5.

13. The baby shampoo formulation of claim 12 wherein the solids concentration is from 10% to 25%.

14. The baby shampoo formulation of claim 12 wherein the composition also contains a polyol.

15. The baby shampoo formulation of claim 14 wherein the polyol is glycerin, propylene glycol, or sorbitol at a concentration of from 2 to 2.5 wt. %.

16. The baby shampoo formulation of claim 12 wherein the polyglyceryl ester is an ester of a straight-chain fatty acid.

17. The baby shampoo formulation of claim 12 wherein the polyglyceryl ester is a decaglyceryl monooleate or monosun-flower-ate ester.

18. The baby shampoo formulation of claim 12 wherein the zwitterionic surfactant is a betaine.

19. The baby shampoo formulation of claim 12 wherein the anionic surfactant is sodium lauryl sulfate, the zwitterionic surfactant is cocamidopropyl betaine, a sodium cocoamphoacetate, or a disodium cocoamphodiacetate.

20. A shampoo formulation which comprises:
(a) from 5 to 20 wt. % of an anionic surfactant;
(b) from 1 to 10 wt. % of a polyglyceryl ester having the formula:
R5OCH2-CH(OR4)-CH2-(O-CH2 CH(OR3)-CH2)n-O-CH2-CH(OR2)-CH2OR1 wherein n is from 4 to 14 and one or more R groups is an acyl group containing from 8 to 22 carbon atoms and the remaining R groups are hydrogen;
(c) from 0.1 to 10 wt. % of a non-volatile sili-cone;
said formulation having a viscosity in the range of from 3000 to 8000 centipoise and a pH in the range of from 6.5 to 7.5.

21. The shampoo formulation of claim 20 wherein the composition also contains a polyol.

22. The shampoo formulation of claim 21 wherein the polyol is glycerin, propylene glycol, or sorbitol at a concen-tration of from 0.5 to 10 wt. %.

23. The shampoo formulation of claim 20 wherein the polyglyceryl ester is an ester of a straight-chain fatty acid.

24. The shampoo formulation of claim 20 wherein the polyglyceryl ester is hexaglyceryl distearate or dilaurate.

25. The shampoo formulation of claim 20 wherein the anionic surfactant is sodium lauryl sulfate.